Effect of FSW Parameters on Hook formation, Microstructure and Fracture Strength of Al, Mg alloys

  Shubhavardhan R N,  M.M Rahman

Friction stir welding (FSW) is a solid-state joining technique which can be used for joining not only traditionally wieldable aluminum alloys but also high strength aluminum and other metallic alloys that are hard to weld using conventional fusion welding processes. During (friction stir lap welding) FSLW of similar metallic alloys, a part of the original lapping interface between the plates is lifted up due to a specific material flow induced by the rotating threaded tool pin, taking a hook shape. Such a hook in a FSL welds often provides a favorable site for crack propagation under loading and thus adversely affects σLap. Furthermore, FS heat causes local softening but grain refinement by dynamic recrystallization contributes to hardening in stir zone. Thus strength is location dependent. The nature (shape and continuity) of hooks in FSL welds of similar alloys have not been discussed well in literature. Thus, the aim of the present research is to provide thermomechanical explanation on how ω and ν affects hook formation during FSLW; to understand how hooking, FS softening, stress concentration and local deformation mechanisms (under loading) relate to fracture strength of Al and Mg FSL welds.

Keywords- Aluminum alloy, Magnesium alloy, Friction stir lap welding, Fracture strength, FSW parameters

Unique Identification Number - IJEDR1702272
Page Number(s) - 1730-1736
Pubished in - Volume 5 | Issue 2 | June 2017
DOI (Digital Object Identifier) -   
Publisher - IJEDR (ISSN - 2321-9939)

  Shubhavardhan R N,  M.M Rahman,   "Effect of FSW Parameters on Hook formation, Microstructure and Fracture Strength of Al, Mg alloys", International Journal of Engineering Development and Research (IJEDR), ISSN:2321-9939, Volume.5, Issue 2, pp.1730-1736, June 2017, Available at :http://www.ijedr.org/papers/IJEDR1702272.pdf